BCHM 30700 1st Edition Final Exam Study Guide Lectures 28 40 Lecture 28 April 1 What are the first and second laws of thermodynamics The first law is that energy cannot be created or destroyed it can only be converted from one form to another The second law is that all systems tend to become more disorganized What are exothermic isothermic and endothermic reactions Exothermic reactions release heat Isothermic reactions don t give off heat Endothermic reactions absorb heat What does G tell you When G is negative the reaction is spontaneous When G is positive the reaction is nonspontaneous Lecture 29 April 3 What is catabolism and anabolism Catabolism is the breakdown of large molecules to smaller ones Anabolism is the synthesis of large molecules from smaller ones What is a redox reaction One molecule is oxidized and loses electrons This molecule in turn gives up its electrons to another molecule The molecule that gains electrons is reduced What is the energy currency within cells ATP is the energy currency It is not the energy storage in cells though ATP has a high turnover rate Lecture 30 April 6 What does glycolysis start with and end with Glycolysis starts with glucose and adds in ADP inorganic phosphate and NAD It produces pyruvate ATP and NADH Which steps of glycolysis are irreversible The kinase reactions are reversible These are steps 1 2 and 10 What types of reactions occur in glycolysis Isomerization phosphoryl group transfer and nonhydrolytic cleavage Lecture 31 April 8 What is alcoholic fermentation This occurs in yeast cells It only occurs in the absence of oxygen It starts with pyruvate and ends with ethanol What is anaerobic glycolysis This occurs in our muscle tissues This occurs in the absence of oxygen This starts with pyruvate and forms lactate This process is called the Cori cycle which cycles through the muscles and liver What is gluconeogenesis This is the resynthesis of glucose from glycolytic intermediates This process is very similar to glycolysis It employs 4 new steps to accommodate the irreversible ones of glycolysis Lecture 32 April 10 What is the citric acid cycle equation including pyruvate dehydrogenase Pyruvate 4 NAD FAD GDP Pi 2 H2O yields 3 CO2 4 NADH 4H GTP FADH2 Where does the citric acid cycle occur It occurs in the matrix of the mitochondria in eukaryotes In prokaryotes it occurs in the cytosol Lecture 33 April 13 What is the pyruvate dehydrogenase complex This complex links glycolysis to the citric acid cycle It is made up of several enzymes clustered together Its function is to convert pyruvate to acetyl CoA through coenzyme A What does the citric acid cycle produce It produces NADH hydrogen ions and FADH2 These are used to produce ATP Lecture 34 April 15 What can the citric acid cycle form through anabolism Citrate is used to form fatty acids and cholesterol Alpha ketoglutarate is used to make amino acids Malate is used to form pyruvate Succinyl CoA is used to form hemes Oxaloacetate is used to make glucose What is the electron transport chain It is used to capture the energy in the redox potential of NADH and FADH2 The energy produced is used to produce ATP Where is the electron transport chain located It is in the mitochondrial inner membrane It includes integral and peripheral membrane proteins This proteins contain metals or flavins Lecture 35 April 17 What is complex I It is also called NADH ubiquinone oxidoreductase It contains a flavoprotein with a Fe S centers It only passes one electron at a time It has two centers for oxidation reduction reactions What is complex II This is also called succinate dehydrogenase It is also a part of the TCA cycle This contains two centers for oxidation and reduction What is complex III It contains several cytochromes It also contains Fe S center proteins What is complex IV It contains two cytochromes It also contains proteins with copper centers This complex reduces oxygen to water Lecture 36 April 20 What is the purpose of the complexes They pump protons across the inner mitochondrial membrane This generates a membrane potential The first and third complexes pump out 4 hydrogen ions The fourth complex pumps out 2 hydrogen ions What is the ATP synthase complex It is a large transmembrane complex It generates one ATP for every three protons that pass through it The oxidation of NADH generates 3 ATP The oxidation of FADH2 generates 2 ATP Lecture 37 April 22 What compounds can block the electron transport chain Complex I is inhibited by rotenone Complex II is inhibited by antinmycin A Complex IV is inhibited by cyanide azide and carbon monoxide What does 2 4 dinitrophenol do It is a hydrophobic molecule It can diffuse through the mitochondrial inner membrane It dissipates the proton gradient This uncouples the electrochemical gradient from ATP synthesis Lecture 38 April 24 What are heterotrophs They are organisms that ingest plants and animals They oxidize organic compounds to create ATP What are phototrophs They absorb radiation from the sun and divert the energy through electron transport chains This makes ATP and reducing power in the form of NADPH What does transduction depend on 1 The sequential redox reactions that pass electrons from water to NADPH 2 The compartmentalization of these reactions in the chloroplast 3 The generation of a proton gradient from the above Lecture 39 April 27 Where does the photosynthetic electron transport chain occur in plants It occurs in the thylakoid membrane Chlorophyll and accessory pigments funnel energy towards the photosynthetic reaction center What are light reactions They are reactions that use light directly They start of using water The redox potential of the electrons is elevated What are photosystems They are clusters of pigments that absorb light The second photosystem is called P680 and the first photosystem is called P700 Lecture 40 April 29 What happens in the Z scheme 1 2 3 4 5 6 Plastoquinone reduces the cytochrome B6f complex Cytochrome b6f complex reduces plastocyanin Plastocyanin shuttles electrons to reduce PS I PS I absorbs a photon of light PS I reduces ferredoxin Ferredoxin reduces NADP What are dark reactions They occur in the stroma of the chloroplast They are called dark reactions because they don t use light directly but indirectly These reactions use ATP and NADPH to fix CO2 into an organic form What happens in the dark reactions RUBISCO catalyzes the first fixation of carbon The fixed CO2 is regenerated at the end The final product is